تعيين ويژگي هاي شيردهي ، تركيبات شير ميش ها و رشد بره هاي نژاد شال و زندي

Determination of lactation performance, milk composition and lamb growth in shall and Zandy ewes

Milk production and composition of 2-3 years old ewes from two Iranian breeds (Shall, n-20; and Zandi, n---19), giving birth of single Iambs were studied. Average lactation length and milk yield were 119 days and 110.3 kg for shall, and 91 days and 40.95 kg for Zandi ewes. Ewe age (2 and 3 years) had not a significant effect on total milk production. The ewes suckling ram lambs produced more milk (114.3+1.96 kg for shall and 43.4±1.80 kg for Zandy) compared with those suckling ewe lambs (106.3±1.60 kg for shall and 38.2± 1.1 1 kg for Zandy) (P<0.05). Average daily gain and total weight gain were greater for the ram lambs than for the ewe lambs and the difference in shall was significant (P<0.0I ). The weaning weight of ram Iambs in both breeds were higher than ewe lambs (P<0.()1). The mean fat content of the milk was 5.85 and 6.080%, the mean protein content was 5.50 and 5.45%, the mean lactose content was 5.03 and 4.52% and the mean non-fat solids content was 11.77 and 11.55% in Shall and Zandi ewes respectively.